This white paper explains how ul 508a supplement sb is used to determine panel sccr and how. Shortcircuitbased configuration of the industrial control panel shall be performed by the manufacturer. Prior to the release of the latest edition of ul 508a, supplement sb dated december 20, 20, sccr applied only to the power circuit of a control panel. Ul standard for safety for industrial control panels. Ul 508a standard pdf download gaaphakerslingbeachs blog. Global control panel design industrial control panel. All components in power circuit must have ratings ratings of starters are typically based on hp rating supplement sb, table sb4. Nec article 409 and ul 508a shortcircuit current ratings sccr.
Ul 508a certification is an industrial control panel directive, which is sought by electrical inspectors. Page ul enclosed sccr 1 air ul 508a ul 508a 1995 376. This guide is not intended to be used in lieu of ul 508a or other regulatory standards. Calculating shortcircuit current rating control panel. The ul listing mark on an industrial control panel provides evidence of third party certification to the municipal inspection authority and to the purchaser of the panel. Design of a motor circuit as per standard ul 508 part iv and ul 508a chap. Always consult all pertinent actual regulatory standards and local standard representatives to ensure full compliance. Equipment intended to be connected to a source of supply greater. Join us for a 3hour training session on equipment shortcircuit current ratings sccrs and national electrical code nec requirements, understanding industrial control panels devices, and ul 508a supplement sb. Ul 508a supplement sb provides a method of assigning the sccr to an icp based on the types of overcurrent protective devices and the ratings of components used within the panel. The power circuit supplies electricity to the workers that do the heavy lifting, powering large motors, for example.
Basic steps for calculating the sccr of a control panel. Each copy is watermarked with the purchasers information. This method is based upon the weakest link approach. Formerly supplement sa of ul 508a 1 listed components 1. With the numerous possibilities for product combinations within a panel, this option will require a tremendous investment in testing and maintenance. Underwriters laboratory 508a overview of ul508a supplement sb ul 508a is a safety standard for industrial control panels adopted by underwriters laboratory, which is an approved method in determining sccr referenced by nec article 409.
Purchase ul standards online official ul standards sales. Control panel technical guide how to ensure troublefree approval of your ulcompliant control panels 8 2 ul standards and circuit design design of a motor circuit as per standard ul 508 part iv and ul 508a chap. While that seems a reasonable request, and is certainly in the best interest of safety, in practice it can be difficult to comply with. Nec requirements for shortcircuit current ratings iaei. Once the file has opened, it will be locked to the users computer. This white paper explains how ul 508a supplement sb is used to determine panel sccr and how the use of typetested components and current.
Nec article 409 and ul 508a shortcircuit current rating sccr of industrial control panels. Ul508a supplement sb4 is the approved method for determining short circuit. Purcell systems manufactures ul 508a certified enclosures and cabinets to the ul 508a safety standard this manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent damage to property. This is typically somewhere between 240vac 600vac, 3 phase power. Ansiul 508a, standard for industrial control panels, supplement sb, is an example of an approved method. Latest facebook app for nokia s40 latest facebook app for n. Underwriters laboratory implemented ul508a supplement sb to.
Ul 508a industrial control panels power distribution and. Tested product combinations to meet nec article 409 and ul. Determine the sccr of all individual power components and ul approved series ratings. Ul now offers the ability to purchase a premium hard copy of any ul standard. June 2018 55 may 2018 90 april 2018 36 march 2018 35 february 2018 28 january 2018 24 december 2017 17 november 2017 17. Underwriters laboratory implemented ul508a supplement. For each, protection and control functions are stipulated. Ul 508a online certifications directory outline of ul 508a slide 3 industrial control procedure ul508a descriptive procedure part 1 general use supplement sa specific component requirements part 2 specific use information you provide specific components not. Jul 07, 2015 in 2005 ul 508a was changed to require control panel builders to include a short circuit current rating on the control panel assembly. Overview of code changes in nec article 409 overview of ul 508a supplement sb. Because electrical design stands ul and iec differ, it can be challenging to meet all market requirements in a single design. The second day instructs industrial control panel customers on how to establish shortcircuit ratings for individual industrial control panels in accordance with the requirements outlined in the new standard for industrial control panels, ul 508a, 3rd edition, supplement sb. A brief history of ul 508a and tips for how control panel. Shortcircuit current rating application and codes training.
A ul 508a certification is an industrial control panel directive, which electrical inspectors look for. Ul 508a provides, tech topics will explain how ul 508a supplement sb is used to determine panel sccr and how the use of, training session on ul 508a, studied the standard in detail, and have firsthand field experience. The ul 508a listing mark on an industrial control panel provides evidence of third party certification to the municipal inspection authority and to the purchaser of the panel. Sccr rating marked on the component use assumed sccrs in table sb 4. With the release of the ul 508a, ul standard for safety for industrial control panels, an industryapproved method is now available. Our icp shop program allows manufacturers who custom build or massproduce icps in the u. Ul 508a standard pdf download a1d9fc608e share on facebook in industrial control panels according to ul508a. The table below is extracted from the ul 508a supplement sb, table sb4. Ul 508a supplement sb sccr method ul 508a supplement sb describes three steps to determine the sccr of industrial control panels. Ul 508a, supplement sb, provides an analytical method to determine the shortcircuit current rating of an industrial control panel. Ul 508a supplement sb is the preferred option for nearly all industrial control panels. Underwriters laboratory implemented ul508a supplement sb.
Once you have all of the component ratings, either use an outside service or ul 508a supplement sb. Evaluate panel per ul508a, supplement b required by 406 if jurisdiction does not adopt 2005 nec earlier. This supplement is the only method specifically noted as being. Determining sccr for industrial control panels and. Control panels containing predominately communication equipment, such as telephone equipment and intended for installation in accordance with chapter 8 of the nec, is evaluated to the standard for information technology equipment safety. Determine the sccr of all individual power components by one of the following methods. Ul 508a covers industrial control panels and industrial panel enclosures operating at 600. Supplement sb says that the sccr of an icp is equal to the sccr of the. We design, assemble, and install ul certified panels and can bring existing control panels up to ul safety standards, as well as build panels from the ground up meeting the customer requirements, while following ul safety standards. How to determine shortcircuit current ratings iaei magazine. In the case of a motor feeder, a number of component combinations may be used to ensure the functions, however. Equipment sccr, industrial control panel devices and ul 508a supplement sb. The sccr requirements for ul 508a are effective after april 25, 2006.
Each license entitles a user to download the file to their pc and print 1 copy. Ul 508a supplement sb ul508a is a safety standard for industrial control panels adopted by underwriters laboratory which is an approved method in determining sccr referenced by nec article 409. How to ensure troublefree approval of your ulcompliant. Underwriters laboratory implemented ul 508a supplement sb to require compliance by ul authorized panel builders. The process for ul 508a, supplement sb analyzes the sccr for power circuit components, determines if these ratings can be raised by currentlimiting devices in the feeder circuit, and compares the lowest component rating with the lowest interrupting rating of overcurrent devices to determine the assembly sccr. Shortcircuit current rating markings are not required for industrial control panels containing only control circuit components. Ul 508a industrial control panels power distribution and control. Ul 508a standard pdf download a1d9fc608e share on facebook. The industrial control panel shall be designed so that it supports the specified sccr. Ul 508a covers industrial control panels and industrial panel enclosures operating at 600 volts. Do you design and build industrial control panels or machinery that is used across the world. Please refer to the ul website to view the most uptodate table sb4.
Supplement sb is the ul approved method for determining the sccr for industrial control panels based on the power circuit components within the. Ul 508a provides analytical method for determining panel. Overview of supplement sb from the ul 508a standard. Shortcircuit calculation control panel tips siemens global. Requirements for industrial control panel safety, implications of ul 508a 2nd edition. Please allow ample time for delivery through the us postal service. Studio 5000 faq, goodbye legacy l4x controllers, graceport. Ansi ul 508a, standard for industrial control panels, supplement sb, is an example of an approved method. Ul 508a, supplement sb is an approved method to determine sccr for industrial control panels and industrial machinery control panels. Industrial control panels and the panel shop program. Ul 508a supplement sa specific component requirements. Identify the lowest component sccr andor component combination sccr rating with an overcurrent protective device ocpd.
Reference manual shortcircuit current rating sccr of. Modify the sccr of certain series combinations if currentlimiting devices are used in the feeder circuit. Test each panel construction and record the construction in a followup procedure. In 2005 ul 508a was changed to require control panel builders to include a short circuit current rating on the control panel assembly. Ul 508a standard for industrial control panels purcell systems.
Control panels containing predominately communication equipment, such as telephone equipment and intended for installation in accordance with chapter 8 of the nec, is evaluated to the standard for information technology equipment safety part 1. Ul 508a, but is by no means an exhaustive guide, and does not cover all uses and applications associated with ul 508a regulations. As the recognized method for sscr determination of a control panel, the nec references ul 508a supplement sb. With standardization, we can help you achieve a global design that is fit for all markets while saving on engineering time and costs. Requirements for industrial control panel safety, conductors. Requirements for industrial control panel safety, implications of ul.